A mass spectrometer system, comprises: an ion source; a first and a second multipole apparatus; one or more ion gates or ion lenses between the first and second multipole apparatuses; at least one power supply configured to provide voltages to electrodes of the ion source, the mass analyzer, the first and second multipole apparatuses and the one or more ion gates or ion lenses; and a computer or electronic controller electrically coupled to the at least one power supply, wherein the computer or electronic controller comprises computer-readable instructions that are operable to cause the at least one power supply to supply voltages to the electrodes that cause transfer of ions from the first multipole apparatus to the second multipole apparatus, wherein a duration of a time allotted for completion of the transfer of the ions is dependent upon one or more properties of the ions being transferred.

A mass spectrometer is disclosed comprising: a first vacuum chamber having an inlet aperture; a second vacuum chamber; a differential pumping aperture separating the vacuum chambers; and an ion guide arranged in the first vacuum chamber for guiding ions from the inlet aperture to and through the differential pumping aperture. The ion guide has a construction for handling high gas loads such that the spectrometer is able to maintain the gas pressure in the first vacuum chamber such that when ions are accelerated therethrough the ions collide with gas and fragment.

A method of operating a collision cell (10) in a mass spectrometer is disclosed. The collision cell comprises an entrance aperture (116), an exit aperture (117) and electrodes (113, 114) for producing electric fields. The method comprises feeding ions in a forward axial direction (LD) through the entrance aperture into the collision cell, producing a first electric field to trap ions, and subsequently producing a second electric field to accelerate trapped ions in the forward axial direction. The method further comprises producing a gas flow (G1) which is, at least at the entrance aperture (116) of the collision cell, contrary to the forward axial direction (LD), so as to reduce the kinetic energy of ions in dependence on their collisional cross sections. A collision cell arranged for carrying out the method is also disclosed, as well as a mass spectrometer comprising such a collision cell.

Provided is a mass spectrometer including: a measurement condition setter (42) configured to set a plurality of measurement conditions which are different from each other in terms of the set value of at least one measurement parameter; a measurement executer (43) configured to acquire a plurality of sets of mass spectrometric data respectively corresponding to the plurality of measurement conditions; a product ion extractor (44) configured to extract product ions detected with intensities exceeding a previously determined reference value; an MRM spectrum element information creator (45) configured to determine the mass-to-charge ratios and measured intensities of the extracted product ions, the mass-to-charge ratio of the precursor ion, as well as the measurement condition, and to create a plurality of pieces of MRM spectrum element information; an MRM spectrum composer (46) configured to compose an MRM spectrum from the mass-to-charge ratios and the measured intensities of the product ions included in the plurality of pieces of MRM spectrum element information; and a library data creator (47) configured to relate the MRM spectrum to information concerning the target compound to create library data for the target compound.

Methods are described for measuring the amount of C peptide in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying C peptide in a sample utilizing on-line extraction methods coupled with tandem mass spectrometric or high resolution/high accuracy mass spectrometric techniques.

An analysis method includes: performing liquid chromatography using a mobile phase including an adsorption prevention agent for preventing adsorption of a sample including a compound having a phosphate group to metal; and performing mass spectrometry on an eluate of the liquid chromatography. The adsorption prevention agent includes an oxalic acid or a salt of the oxalic acid.

A method of mass spectrometry for analyzing a sample within a mass range of interest includes the steps: ionizing the sample to produce a plurality of precursor ions; performing an MS1 scan of the precursor ions comprising mass analyzing the precursor ions across the mass range of interest, to obtain an MS1 mass spectrum of the precursor ions; determining ion intensity values within the MS1 mass spectrum; selecting precursor mass segments within the mass range of interest, and for each precursor mass segment: fragmenting the precursor ions within that precursor mass segment; and performing an MS2 scan of the fragmented ions by: controlling an amount of fragmented ions for that precursor mass segment, based on an intensity value for that precursor mass segment derived from the MS1 spectrum; and mass analyzing the amount of fragmented ions.

In a chromatograph mass spectrometer having a measurement unit (1) including a chromatograph is combined with a tandem mass spectrometry section capable of an MS/MS analysis, a controller (40) performs chromatograph mass spectrometry by controlling the measurement unit so as to operate the tandem mass spectrometry section to cyclically perform analysis cycles, where each of the analysis cycles includes a first mass spectrometric analysis in which a measurement of ions is performed over a predetermined m/z range and an MS/MS analysis by DIA in which ions included within each of a plurality of windows formed by dividing the m/z range are designated as a precursor ion. A window selector (42, 43) selects, during an execution of an analysis cycle, a window among the plurality of windows for an MS/MS analysis by DDA which is irregularly performed in an ongoing analysis cycle, based on intensity information obtained for each of the plurality of windows from an MS/MS spectrum acquired by the MS/MS analysis by DIA. A precursor-ion determiner (44) determines a precursor ion corresponding to the window selected by the window selector in a mass spectrum acquired by the first mass spectrometric analysis in the ongoing analysis cycle, based on peak information included within the m/z range of the window. A data-dependent-acquisition condition setter (45) informs the controller of the precursor ion determined by the precursor-ion determiner, as the precursor ion for the MS/MS analysis by DDA which is irregularly performed in the ongoing analysis cycle.

The present disclosure generally relates to methods for determining chemical class compositions present in a sample using collision cross-section fragment ion values.

A mass spectrometry method comprising steps of generating an ion beam from an ion source; directing the ion beam into a collision cell; introducing into the collision cell through a gas inlet on the collision cell a charge-neutral analyte gas or reaction gas; ionizing the analyte gas or reaction gas in the collision cell by means of collisions between the analyte gas or reaction gas and the ion beam; transmitting ions from the ionized analyte gas or reaction gas from the collision cell into a mass analyzer; and mass analyzing the transmitted ions of the ionized analyte or reaction gas. The methods can be applied in isotope ratio mass spectrometry to determine the isotope abundance or isotope ratio of a reaction gas used in mass shift reactions between the gas and sample ions, to determine a corrected isotope abundance or ratio of the sample ions.